NAME

SYNOPSIS

DESCRIPTION

The argument cd must be a conversion descriptor
created using the function iconv_open.

The main case is when inbuf is not NULL and
*inbuf is not NULL. In this case, the iconv
function converts the multibyte sequence starting at
*inbuf to a multibyte sequence starting at
*outbuf. At most *inbytesleft bytes, starting
at *inbuf, will be read. At most *outbytesleft
bytes, starting at *outbuf, will be written.

The iconv function converts one multibyte
character at a time, and for each character conversion it
increments *inbuf and decrements *inbytesleft
by the number of converted input bytes, it increments
*outbuf and decrements *outbytesleft by the
number of converted output bytes, and it updates the
conversion state contained in cd. If the character
encoding of the input is stateful, the iconv function
can also convert a sequence of input bytes to an update of
the conversion state without producing any output bytes;
such input is called a shift sequence. The conversion
can stop for four reasons:

1. An invalid multibyte sequence is encountered in the
input. In this case it sets errno to EILSEQ
and returns (size_t)(−1). *inbuf is left
pointing to the beginning of the invalid multibyte
sequence.

2. The input byte sequence has been entirely converted,
i.e. *inbytesleft has gone down to 0. In this case
iconv returns the number of non-reversible
conversions performed during this call.

3. An incomplete multibyte sequence is encountered in the
input, and the input byte sequence terminates after it. In
this case it sets errno to EINVAL and returns
(size_t)(−1). *inbuf is left pointing to the
beginning of the incomplete multibyte sequence.

4. The output buffer has no more room for the next
converted character. In this case it sets errno to
E2BIG and returns (size_t)(−1).

A different case is when inbuf is NULL or
*inbuf is NULL, but outbuf is not NULL and
*outbuf is not NULL. In this case, the iconv
function attempts to set cd’s conversion state
to the initial state and store a corresponding shift
sequence at *outbuf. At most *outbytesleft
bytes, starting at *outbuf, will be written. If the
output buffer has no more room for this reset sequence, it
sets errno to E2BIG and returns
(size_t)(−1). Otherwise it increments *outbuf
and decrements *outbytesleft by the number of bytes
written.

A third case is when inbuf is NULL or
*inbuf is NULL, and outbuf is NULL or
*outbuf is NULL. In this case, the iconv
function sets cd’s conversion state to the
initial state.

RETURN VALUE

The iconv function returns the number of
characters converted in a non-reversible way during this
call; reversible conversions are not counted. In case of
error, it sets errno and returns
(size_t)(−1).